The Paris Climate Talks Will Be a Historic Success. And a Historic Disaster.

Here’s how to think about what happens in Paris over the course of the next two weeks: The conference isn’t the game — it’s the scoreboard.

Diplomats, heads of state, activists — they’ll all be descending on the French capital over the next few days (though in smaller numbers than expected before the horrific attacks in the city earlier this month). It will be a three-ring circus, overseen by 3,000 reporters — and the United Nations notified a thousand more last week that there was no more room. There will be congressional delegations, indigenous delegations, and delegations of peasant farmers. There will be oil lobbyists, coal lobbyists, and automobile lobbyists. There will be frantic negotiations that break down and restart and then break down again. And there will be some genuinely important decisions.

But for the most part the decisions have already been made. The action happened not in Paris, but in the streets and in engineering labs over the last half-decade and has changed the equation markedly since the failed talks at the Copenhagen climate conference in 2009. Those talks weren’t just a failure, they were a fiasco — the world’s leaders came together and then came apart, with bizarre and frantic improvised meetings that produced a one-page memorandum with no targets or timetables. No nothing, except a vague pledge to keep the planet’s warming below 2 degrees Celsius. It made Munich look like a diplomatic masterstroke.

Paris will go better. Not well enough to save the planet, but maybe just well enough to save our chances of saving the planet. Here’s why.

First, engineers have upped their game. It’s been remarkable to watch the sudden acceleration of renewable technology in the last five years. We aren’t talking technical breakthroughs — we’re talking quantum improvements in manufacturing and installation: Germany’s smart decision to lead the renewables revolution led to Chinese manufacturers learning how to make cheap panels, which in turn led to tomorrow’s hoped-for technology becoming today’s no-brainer. The price of a solar panel has dropped over 80 percent since 2008. That’s the key destabilizing economic fact of our moment.

And it means that much is possible we couldn’t have dreamed of just a few years ago. Developing countries are suddenly starting to leapfrog the fossil fuel age or at least demonstrate it can be done. Bangladesh — Henry Kissinger’s original “basket case” of a developing country — will be the planet’s first fully solarized nation by 2020 or so. Its well-developed micro-credit networks are now funding 60,000 or 70,000 rooftop solar arrays a month, spreading electricity to places where a hundred years of fossil fuel could never reach. In Rwanda, a single newly inaugurated solar farm boosted Rwanda’s grid capacity by 6 percent — and it was designed, built, and connected in a single year. In India, solar power plants beat coal-fired stations for new contracts — they’re cheaper, even if you don’t include all the externalized costs of fossil fuel (which in, say, Delhi include irreversible lung damage for half the city’s children).

The same arguments apply even in the rich world, where companies like Apple and Google increasingly promise they’ll power their server farms on 100 percent clean energy. The energy forecasters annually underestimate — often by ludicrous margins — how fast renewable energy will spread. And in the process the overwhelming political power of the fossil fuel industry is being slowly undercut by the rise of new powers. Already there are more than twice as many solar workers as coal miners in America; that is beginning to rewrite the political narrative in the world’s biggest economy.

Adding to this momentum is the explosive growth of the climate movement, the great emergent social force of the 21st century. Before Copenhagen, there was nothing. I helped organize a climate march in 2006 in Vermont — it drew just a thousand people, including Bernie Sanders, in his pre-presidential-candidate days. The press said it was likely the largest climate march that had yet taken place in the United States. But in the years since, 350.org, which I helped found, has organized 20,000 demonstrations in every country but North Korea, and some of them have been huge: The 400,000 people who thronged the streets of Manhattan in September 2014 were part of the biggest demonstration about anything in this country in many years.

That movement has begun to claim real victories. It convinced President Barack Obama to stop the Keystone pipeline, which was the first time a world leader had rejected a big project because of its effect on the climate. More importantly, that effort spawned a thousand other fights, in what one beleaguered fossil fuel industry lobbyist called the “Keystone-ization” of every other project on the continent. In Australia, activists have thrown a wrench into plans for one of the world’s largest coal mines; in Germany they invaded Europe’s biggest coal fields; in the Arctic they helped drive first Shell and then Statoil away from the oil and gas fields. Fracking has been banned in big U.S. states and major countries. As of Paris, endowments and portfolios representing at least $5 billion in assets have been divested from some or all fossil fuels. (Most recently, it was the world’s largest insurance company, Germany’s Allianz, pulling its capital out of coal.)

That surging political movement has changed the conversation and made climate change a front-burner topic. Obama and Hillary Clinton were able to come home failures from Copenhagen and pay no price; that’s not true for Paris nor for most other leaders. They need to show progress.

And they will. In fact, we already know how much. Since there’s not going to be a real treaty (no one on earth thinks the U.S. Senate would actually approve a binding document), the promises laid out in advance by various nations already tell us what the scoreboard will read come Dec. 11, though some details remain to be hashed out. Instead of a world that will become 5 degrees warmer — our post-Copenhagen trajectory — we’ll come out of Paris with promises from individual nations that, when you add them up, would warm the planet 3.5 degrees if they were kept.

That’s historic, that’s remarkable — and that’s also a disaster. A world that warms 3.5 degrees would not be a world with civilizations that resemble ours. In fact, even the longtime negotiating goal of 2 degrees (the only thing that participants in Copenhagen actually agreed on) is clearly too high. We’ve heated the planet 1 degree so far since the industrial age began, and the U.N. said in November that that has produced a world where 4.1 billion people have been affected by extreme weather disasters over the last 20 years. So far this fall we’ve seen the highest windspeeds and the lowest barometric pressure ever recorded in a storm in the Western Hemisphere. We’ve seen two rare cyclones plow into Yemen — and they came a week apart, dropping the normal equivalent of 10 years of rain in a few hours. We’ve seen — well, I could go on. The point is, 1 degree has been enough to melt most of the summer sea ice in the Arctic, fundamentally destabilize the Antarctic ice sheets, and make the oceans 30 percent more acidic. And we’re hoping for 2 degrees? And aiming for 3.5?

Paris could still contribute to improving this picture on the margins. There are two items on the docket still to be decided.

The first is the amount of aid for poor countries trying to become solar and wind-powered. It’s clearly both morally and practically sound for rich countries to provide that aid: Nothing would be more foolish than insisting Africa go through the coal age. But of course the fossil fuel industry is doing its best to block progress — in November the Senate voted against even the exceedingly modest $500 million the Obama administration proposed as our contribution. This defines shortsightedness; it’s hard to imagine any diplomat making a coherent argument for not helping out, especially when we’ve contributed the plurality of the atmosphere’s anthropogenic carbon dioxide. But apparently that’s politics circa 2015.

Second, there will be an effort to build in a “ratchet mechanism” that automatically reviews the national pledges and pushes them upward as the condition of the climate worsens. This would make it easier to keep progress on track, instead of the huge effort to build the diplomatic head of steam necessary to get Paris off the ground.

After Copenhagen, the scoreboard read: Fossil Fuel Industry, 50; Planet and Physics, 0. Call that halftime.

After Paris, the score will be more like 60-30. Reality is beginning to catch up, but it’s not halftime anymore. We hope it’s the end of the third quarter, but there’s reason to believe it’s actually much later in the game. 2015 looks set to be the hottest year ever recorded and October the hottest month we’ve ever measured — indeed it smashed the old record by such large margins that nervous climatologists called it “stunning,” “shocking,” and potentially the start of a new, even more dangerous, phase for the planet’s temperature.

So that’s Paris. We won’t win the climate fight; we won’t even come close. But at least we’ll know the score — and we’ll know how much we have to do in the next few crucial years.

Photo credit: AFP/Getty Images